1. Field of Invention
The present invention relates to an electricity supply system, in particular to an lithium battery using a circuit substrate as a separator.
2. Related Art
In the electronic device industry, portability is one of the major trends. A portable electronic device typically requires an electricity supply system/module to supply electricity for functional components/modules. Typically, electricity supply modules (e.g., a battery module) and functional modules (e.g., a module including one or more of memory, computing, and display components) are implemented in separate units, as illustrated in the example of FIG. 1.
FIG. 1 illustrates a battery 1 configured to supply electricity for a functional module 2. The battery 101, e.g., a lithium battery, typically includes active material layers 12 and 13 configured to perform conversation of chemical energy into electrical energy. The active material layers 12 and 13 are separated by a separator 11 to prevent short circuit between the active material layers 12 and 13.
The battery 1 may further include conductors 14 and 15 configured to collect currents and to form an electrical path between the active material layers 12 and 13 and a functional module 2. The conductors 14 and 15 are electrically coupled with contacts 21 and 22 respectively, of the functional module 2 through tabs 141 and 151 respectively. The contacts 21 and 22, in turn, are electrically coupled with a circuit 23 that includes various components for performing various functions.
The tabs 141 and 151 serve as interfaces between the battery 1 and the functional module 2 (or a charger for the battery 1). Typically, alignment between the tabs 141 and 151 and the contacts 21 and 22 are required to ensure reliable electricity supply. Requirements of precise alignment between the tabs 141 and 151 and the contacts 21 and 22 may incur significant manufacturing costs.
Further, to ensure reliable and stable electricity supply, the relative position between the tabs 141 and 151 and the contacts 21 and 22 need to be maintained. As a result, the combined electronic device that includes the battery 1 and the functional module 1 is unable to be made flexible.
If conductive wires are implemented between the contacts 21 and 22 and the tabs 141 and 151 to provide flexibility, alignment of more contact points are required, and manufacturing costs are increased. Further, the conductive wires may not be able to withstand a large number of a high frequency of bending. Damage to the wires, e.g., resulted from bending, may cause the electronic device to malfunction.
In general, the battery 1 includes a package unit 16 for enclosing various components of the battery 1 to prevent moisture intake and electrolyte leakage of the battery 1. However, the tabs 141 and 151 typically are required to protrude from the package unit 16 to perform interface functions for power supply and recharge. Typically, the package unit 16 is formed of a material that is different from the material of the tabs 141 and 151. Even if sealing means, such as solder, are applied at the junctions of the package unit 16 and the tabs 141 and 151, gaps may still exist at the junctions. Accordingly, the package unit 16 may not be able to effectively prevent electrolyte leakage and moisture intake. As a result, performance of the battery 1 is deteriorated. In order to minimize or eliminate the gaps, the manufacturing and/or material costs of the battery 1 may be increased.
As also can be appreciated from the example of FIG. 1, the battery 1 and the functional module 2 require different packages. The separate packages also incur significant manufacturing and material costs.